Photo Credit: Katerina Holmes on Pexels
Contemplate the difference between synthetic and natural materials that make up common items in the classroom.
Grades 5 and up
Time Needed 30 to 60 minutes
Format Suitable for group or individual learning
Purpose and Context
Every physical object that humans create and use is made of resources provided by planet Earth. Throughout human history, people have invented ways of collecting, modifying and altering nature’s resources.
The resources provided by nature can be categorized into a variety of groups. Things coming from the ground include rocks, minerals, metals, oils and gases. From rocks we isolate metals to make steel, aluminum, copper, and gold. Limestone rocks are transformed into materials for making cement. Fossil fuels are extracted to make gasoline, plastics and a large range of products ranging from paint to cosmetics. From clay we make bricks and ceramics, like plates and coffee cups. From sand, we form glass. We also extract minerals like salts for a range of products from table salt to batteries. We also use nature’s plants and animals as resources. From trees we form wood, paper, and cardboard. From cotton plants we create cotton threads and fabrics. From animals we harvest the meat for food and skin for leather clothing and accessories.
Humans have become so good at modifying nature’s resources to meet our needs. In the last 100 years, we’ve invented a new type of materials: synthetic materials. Synthetic materials are made from natural resources, but the human-made chemical and physical processing turns the natural material into something not found in nature. Synthetic materials include things like plastics, including glues and paints, metal alloys, pharmaceuticals. These synthetic materials have many benefits for human societies. Sometimes they provide cheaper alternatives to natural materials. Sometimes they function better than traditional alternatives. They reduce demand for natural materials which protects more wild space.
Humans are exceptionally good at creating new materials, but we haven’t been as successful at recycling, reusing, and otherwise managing these materials and products as they wear out, break, or lose their usefulness. We’ve always created waste, but before the invention of synthetic materials, the waste we created was more manageable because nature could help recycle and return those natural materials to the Earth. Materials coming from the ground like clay could slowly be returned to the sediment. Materials coming from plants and animals, like cotton and leather, could biodegrade and return to the ecosystem. Metals and glass can be recycled over and over again because the processes involve very high temperatures, and the materials do not degrade much with each cycle. Paper can be recycled or composted. And food and yard waste is compostable.
But synthetic materials are causing a new kind of mess. Because synthetic materials are not found in nature, they can have negative impacts on nature when they become pollution. They are also often hard or impossible to recycle, persist in the environment, and are often associated with hazardous chemicals.
Plastics, for example, are not indefinitely recyclable or biodegradable. Some kinds of plastic aren’t recyclable at all, and most kinds of plastic are very complicated to recycle, to the point where it is more expensive than producing new plastics. Unfortunately, a lot of products made these days combine plastics with natural materials in ways that make them difficult or impossible to separate. Examples of this are Mylar chip bags, plastic lined paper coffee cups, and polyester/cotton blend clothes.
In summary, we urgently need to start treating synthetic materials, and plastics in particular, differently from our other waste materials, to reduce their negative impacts. This starts with improving our awareness of what synthetic materials we use on a daily basis.
Print a scavenger hunt list for each group of 3-5 students.
Group students into groups of 3-5. Give them the scavenger hunt list, and set a timer for 15 minutes to find as many items on the list as possible.
Once time is up, students should sort their items into two piles: 1. Items made of synthetic materials and 2. Items made of natural materials.
Discuss as a class: How did your group define “synthetic” and “natural”? How did your group determine how to categorize the items?
Each student then picks 1 item from their synthetic pile. (Consider extending to 1 item from each pile.) For each item, they should brainstorm and conduct research to answer the following questions on the student worksheet:
- What benefits does the item provide to society?
- What are the main materials that make up this product? (You can use the list in Algalita’s blog post: “Plastics Hidden in Plain Sight”, and also do your own research to find out.)
- What natural resources is this product made from?
- Would you call the materials in this product synthetic or natural? Why?
- Could this item be easily reused?
- Can it be recycled? If not, what will likely happen to this item at the end of its usefulness?
Facilitate a discussion to ask students to share their responses.
Tips and Suggestions
Read Algalita’s blog post: “Plastics Hidden in Plain Sight”. Check out the list at the end to find out some common hidden plastic items.
Unsure what something is made out of?
- Do a quick internet search to identify what that kind of material that item is typically made of.
- Use your senses: touch, sound, lustre (how something reflect light), to help guess what something is made of.
- Plastic can take lots of forms, shapes and colors, and its common to find plastic items made to look like natural materials. For example, vinyl floor boards are often made to look like wood.
It can be overwhelming to know how pervasive plastics are in our world. But knowledge and awareness are the first step to positive change! And there are already many people working on better alternatives to many plastic products.
5-PS 1-3 Make observations and measurements to identify materials based on their properties.
MS-PS 1-3 Gather and make sense of info to describe that synthetic materials come from natural resources and impact society.
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